[PATCH] selftests/exec: Fix build on older distros.

[Vinson Lee <vlee-xCSkyg8dI+0RB7SZvlqPiA@public.gmane.org>]

From: Vinson Lee <vlee-1v8oiQdgUNlBDgjK7y7TUQ@public.gmane.org>

This patch fixes this build error on CentOS 5.

execveat.c: In function ‘check_execveat_pathmax’:
execveat.c:185: error: ‘AT_EMPTY_PATH’ undeclared (first use in this function)
execveat.c:185: error: (Each undeclared identifier is reported only once
execveat.c:185: error: for each function it appears in.)
execveat.c: In function ‘run_tests’:
execveat.c:221: error: ‘O_PATH’ undeclared (first use in this function)
execveat.c:222: error: ‘O_CLOEXEC’ undeclared (first use in this function)
execveat.c:258: error: ‘AT_EMPTY_PATH’ undeclared (first use in this function)

Cc: stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org # 3.19+
Signed-off-by: Vinson Lee <vlee-1v8oiQdgUNlBDgjK7y7TUQ@public.gmane.org>
---
 tools/testing/selftests/exec/execveat.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/tools/testing/selftests/exec/execveat.c b/tools/testing/selftests/exec/execveat.c
index 8d5d1d2..170148d 100644
--- a/tools/testing/selftests/exec/execveat.c
+++ b/tools/testing/selftests/exec/execveat.c
@@ -20,6 +20,16 @@
 #include <string.h>
 #include <unistd.h>
 
+#ifndef AT_EMPTY_PATH
+# define AT_EMPTY_PATH 0x1000
+#endif
+#ifndef O_PATH
+# define O_PATH 010000000
+#endif
+#ifndef O_CLOEXEC
+# define O_CLOEXEC 02000000
+#endif
+
 static char longpath[2 * PATH_MAX] = "";
 static char *envp[] = { "IN_TEST=yes", NULL, NULL };
 static char *argv[] = { "execveat", "99", NULL };
-- 
1.8.2.1